The present invention relates generally to containers for photosensitive media. In particular, the present invention is a roll film canister assembled from components having self-locating features.
Light-tight film canisters are generally known and disclosed, for example, in the Espy U.S. Pat. No. 4,671,409. The Espy canister is configured to hold rolls of photosensitive media such as microfilm used in reader/printers, and includes a tubular sleeve closed at both ends by opaque end caps. The end caps are lockingly interconnected by a rigid tie bar that extends between the end caps through the roll of film. Film is withdrawn from the canister through an elongated exit slot in the sleeve.
The tie bar includes a pair of resilient fingers on each of its opposite ends. During the assembly of the canister, the fingers are deformed under pressure and snapped into central apertures in the end caps. Overlapping strips of plush material such as felt or flocking extend from the opposite sides of the film exit slot to provide a light-tight seal that will not damage the film. The edges of the end caps have exit slot accommodating structures configured to mate with the film exit slot and plush material.
Film canisters of the type described above are typically assembled in red light or darkroom conditions to prevent damage to the film contained therein. These assembly procedures are described generally in the Espy Patent referred to above. Although all the components are press-fit and snapped together, the poor lighting conditions hamper the efficiency of the assembly operation. For example, the assembler will generally have to locate the position of the central aperture in the end cap by hand before snapping the tie rod into the end cap. Furthermore, unless the exit slot accommodating structure on the end cap is properly aligned with the slot on the sleeve, light can enter the canister and damage the film.
It is evident that there is a continuing need for improved film canisters. In particular, there is a need for film canisters that can be easily and accurately assembled under the low light conditions in which these assembly operations are typically performed. The canister must of course be relatively inexpensive to be commercially viable.